ASTM C926-2018 pdf free download

ASTM C926-2018 pdf free download.Standard Specification for Application of Portland Cement-Based Plaster
1. Scope
1.1 This specification covers the requirements for the appli- cation of full thickness portland cement-based plaster for exterior (stucco) and interior work. These requirements do not by default define a unit of work or assign responsibility for contractual purposes, which is the purview of a contract or contracts made between contracting entities. 1.2 This specification sets forth tables for proportioning of various plaster mixes and plaster thickness. N OTE 1—General information will be found in Annex A1. Design considerations will be found in Annex A2. 1.3 The values stated in inch-pound units are to be regarded as the standard. The SI (metric) values given in parentheses are approximate and are provided for information purposes only. 1.4 The text of this specification references notes and footnotes that provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the specification. 1.5 Details of construction for a specific assembly to achieve the required fire resistance shall be obtained from reports of fire-resistance tests, engineering evaluations, or listings from recognized fire testing laboratories. 1.6 This international standard was developed in accor- dance with internationally recognized principles on standard- ization established in the Decision on Principles for the Development of International Standards, Guides and Recom- mendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
3. Terminology
3.1 Terms shall be defined as in Terminologies C11 and C219, except as modified herein. 3.2 Definitions ofTerms Specific to This Standard: 3.2.1 accelerator, n—an admixture that will shorten the setting time of plaster. 3.2.2 admixture, n—a material other than water, aggregate, or basic cementitious material added to the batch before or during job mixing. 3.2.3 acid etching, n—the cleansing and controlled erosion of a solid surface, using an acid wash. 3.2.4 air entrainment, n—the use of an air-entraining ad- mixture or air-entraining cementitious material in a plaster mix to yield a controlled quantity of minute (typically between 10 and 1000 µm in diameter) disconnected air bubbles in the plaster (see entrapped air). 3.2.5 back wrap, n—a means of terminating a polymer- modified, fabric reinforced cementitious base coat by wrapping the reinforcing mesh, which has been affixed to the substrate onto the outboard surface of the foam plastic core to provide continuity of the reinforced base coat and protection for the foam plastic core. 3.2.6 backplaster, n—plaster applied to the face of metal lath opposite a previously applied plaster. 3.2.7 barrier wall, n—type ofwall system that is intended to block or interrupt the movement of water to the interior. 3.2.8 bond, n—the state ofadhesion between plaster coats or between plaster and plaster base. 3.2.9 bonding compound or agent, n—compounds surface applied or integrally mixed with plaster to improve the quality of bond between plaster and plaster base or between plaster coats. 3.2.10 cementitious material, n—a material that, when mixed with water and with or without aggregate, provides the plasticity and the cohesive and adhesive properties necessary for placement and the formation of a rigid mass. 3.2.11 coat, n—a thickness of plaster applied in a single operation. 3.2.11.1 basecoat, n—all plaster applied before the applica- tion of the finish coat. 3.2.12 cold joint (“joining” or “jointing”), n—the juncture of fresh plaster application adjacent to set plaster, in the same plane. 3.2.13 curing, v—the act or processes of producing a mois- ture environment favorable to cement hydration, resulting in the setting or hardening of the plaster. 3.2.14 drainage wall, n—a wall system in which the clad- ding provides a substantial barrier to water intrusion, and which also incorporates a concealed water-resistive barrier over which drainage will occur. 3.2.15 entrapped air, n—unintentional air voids in the plas- ter generally larger than 1 mm. 3.2.16 factory prepared (“mill-mixed” or “ready mixed”), adj—pertaining to material combinations that have been for- mulated and dry-blended by the manufacturer, requiring only the addition of and mixing with water to produce plaster. 3.2.17 fiber, natural or synthetic, n—an elongated fiber or strand admixture added to plaster mix to improve cohesiveness or pumpability, or both. 3.2.18 floating, v—act of compacting and leveling brown- coat plaster to a reasonably true surface plane using a float tool or the act ofbringing the aggregate to the surface offinish-coat plaster. 3.2.19 key (also mechanical key), n—plaster that physically surrounds, penetrates, or deforms to lock onto the perforations or irregularities of the plaster base or previous coat of plaster. 3.2.20 metal plaster base, n—expanded metal lath, or welded or woven wire lath. 3.2.21 plaster, n—portland cement-based cementitious mix- ture (see stucco). 3.2.22 polymer modified cementitious base coat, n—A base coat containing portland cement modified with chemical ad- mixtures (typically polymer latexes) to improve characteristics of the finished product, such as workability, plasticity, water resistance, and adhesion.